Young children who snore have a significantly higher chance of developing behavioral problems when they are older, according to US research published Monday.
A study of more than 11,000 children from birth to seven years old found that youngsters who were affected by sleep breathing problems such as snoring, mouth breathing and apnea were between 40 percent and 100 percent more likely to develop "neurobehavioral problems" by the age of seven.
The study, by researchers at the Albert Einstein College of Medicine of Yeshiva University in New York, was published in the journal Pediatrics.
Lead author Dr. Karen Bonuck said that the findings provided the strongest evidence to date that sleep breathing problems "can have serious behavioral and social-emotional consequences for children."
She added, "Parents and pediatricians alike should be paying closer attention to sleep-disordered breathing [SDB] in young children, perhaps as early as the first year of life."
The researchers said that sleep breathing problems could cause behavioral problems like hyperactivity and "conduct" issues by decreasing oxygen levels and increasing carbon dioxide levels in the brain, interrupting the restorative processes of sleep or disrupting the balance of various brain chemicals.
Co-author Dr. Ronald Chervin added, "Until now, we really didn't have strong evidence that SDB actually preceded problematic behavior such as hyperactivity ... But this study shows clearly that SDB symptoms do precede behavioral problems and strongly suggests that SDB symptoms are causing those problems."
About one in 10 children snore regularly and two to four percent have sleep apnea, according to the American Academy of Otolaryngology -- Health and Neck Surgery.